Diverse reactivity of borenium cations with >N-H compounds

The Ph2P-stabilized borenium 1 reacts cleanly with PhNH2, NH3 and HNTf2 to give a variety of boron compounds, namely the amino-substituted borenium 2 (substitution reaction at B), the neutral phosphine-borane 3, the mixed P/N-stabilized boronium 4 and the dicationic boron species 6. Remote modulation of the Lewis acidity at boron has been studied by preparing the related iPr(2)P-stabilized borenium 7 and reacting it with dihydrogen.